Unheard of medical advice?!

So yesterday I was at the doctors for a couple of different reasons, and while I was there I asked for a repeat prescription for my pill. I explained that I’d had random bleeding during sex but doctor didn’t seem concerned about it. She did, however, tell me that after being on the pill for a while (I’ve been on it since beginning of July) that instead of the typical 21 days on and 7 days off to allow bleeding that it it recommended to shorten that 7 day period to around 4 days. So instead of 21 days on and 7 days off, it will now be 21 days on and 4 days off. She also talked about taking three packs back to back but I was already aware of this.

Just wondering if anyone has ever been advised to do this with shortening their time off the pill? It wasn’t like she was personally recommending it to me but more sounded like it was a common thing to do, but I’ve never heard of this before! Not questioning her knowledge either, just curious.